This actually has nothing to do with lawsuits or fear of legal repercussions. This is about Mary Sue (not the website). Not familiar with Mary Sue? I’m sure you’ve met her before, or her spear counterpart Gary Stu, although they very seldom go by those names. Mary Sue and Gary Stu appear in all kinds of media – books, comic books, television, movies… Mary Sue and/or Gary Stu always know the right thing to say or do and everyone loves them for it. Oddly, while the other characters in whatever media tend to fawn all over Mary Sue and/or Gary Stu, readers/viewers tend to be much less fond of them. This is not true in all cases, and quite often the creator of such media with Mary Sue and/or Gary Stu tend to love them as much as they think everyone else should.
A Sue/Stu is of course one of the worst kinds of characters in media. Often Sue/Stu is an Author Avatar or Author’s Pet, which doesn’t help matters at all. A Sue/Stu is almost more of a caricature than a character since there’s no character development involved and a Sue/Stu generally starts out nearly perfect. The status of a Sue/Stu is somewhat subjective. One person’s Mary Sue is another person’s Bella Swan. Heck, there are even online tests to try to determine the Sue/Stu status of a character.
Here are some of my criteria for determining if I have encountered the dreaded Mary Sue/Gary Stu (which gives me guidelines for traits to avoid when writing my own characters):
1) Practically perfect in every way
Actually, Mary Poppins may be the only Mary Sue I can think of whom I didn’t hate, and whose Mary Sue-ness was in fact central to the movie. But in pretty much other case of a Mary Sue/Gary Stu, the perfection is kind of a byproduct of lazy writing (or Author Avatar). Mary Sue/Gary Stu doesn’t have any real flaws that might actually be interesting in any way. Any flaws they do have are minor, such as being clumsy or perhaps having a slight stutter, and such flaws are supposed to come across as totally adorkable. Yes, I know I’ve protested against heroes with too many flaws, but that’s a different argument. Even if Mary Sue/Gary Stu has a background that should leave them emotionally troubled, they’ve come away from the events stronger and better.
2) Loved by all
Mary Sue/Gary Stu are so perfect and nice with no substantial flaws that everyone loves them. While superficially it may seem as though Mary Sue/Gary Stu’s utter perfection should be annoying, as well as the fact they have mad skillz (see below) and can pretty much do no wrong, that only makes them so much more endearing. In fact, the only people who don’t dote on their every word and deed are usually bad guys. That’s how you can tell they are bad guys! And sometimes even the bad guys secretly love Mary Sue/Gary Stu but they just can’t express it and that’s why they do bad things. Aw, so sad.
3) All the mad skillz
Oh no, the hyperdrive is about to explode and there’s no one who can fix it. The ship is doomed! But wait, Ensign Mary Sue/Gary Stu happen to have studied some obscure theory on hyperdrives and have a plan that’s so crazy it just might work! And of course it does. Obscure arcane text no one can translate? Mary Sue/Gary Stu can! Door only opens for someone of a long-extinct bloodline of sorcerers? Hey, it turns out Mary Sue/Gary Stu are actually descended from the Powerful Sorcerer. Is there anything Mary Sue/Gary Stu can’t do? No, no there isn’t. They can actually do anything and definitely much better than anyone else.
4) Stronger Than Everyone
Not to be confused with “strong as s/he needs to be,” which is a different trope, although Mary Sue/Gary Stu do often fall under this. This is especially egregious with superhero/villain Sues/Stus. The idea is basically that you can throw the entire Justice League/Avengers at this bad guy and s/he just shrugs it off with barely any effort. I’m not talking about Lex Luthor barely compensating for Superman pulling some trick he didn’t think of and emerging victorious. I’m talking about your Prometheus or Harvest or Deathstroke or Green Goblin who take punches to the face by Superman or Luke Cage and just laugh it off. I’m talking about villains who at every turn claim to have anticipated the heroes’ moves so even a defeat is just a minor part of a much larger chess game. Or alternatively, the heroic Sue/Stu who, after the entire League of Awesome Heroes is beat down, pops up with some earth-shattering power that hereforeto hasn’t even been hinted at and saves the day. The power they have defies all internal story logic that has so far been established.
So what’s so wrong with Mary Sue/Gary Stu? Well, ultimately Mary Sue/Gary Stu are very flat characters. They start perfect, continue to be perfect, and end perfect; there is no character development. And since they are so very perfect, there’s never any real drama about whether something bad will happen to them. No matter how much they stutter or trip or walk into danger, they will come through unscathed and probably have saved the day/won the guy/won the girl, or otherwise done something good. Writing Mary Sue/Gary Stu is contrived to make the protagonist so very awesome. Ostensibly the audience is supposed to root for Mary Sue/Gary Stu and love them as much as everyone else. I don’t. I despise Sues/Stus no matter what names or alignment they have. When good guys, I don’t root for them to win, and when bad guys, I just smack my head against a wall in disbelief as they mop the floor with all the heroes.
I actively try to avoid Mary Sue/Gary Stu in whatever guise they take in whatever media they appear in. I also actively try to avoid writing Mary Sue/Gary Stu because such characters are just bad writing.